lkml.org 
[lkml]   [2010]   [Oct]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [patch 03/35] mm: implement per-zone shrinker
Date
Hi

> Index: linux-2.6/include/linux/mm.h
> ===================================================================
> --- linux-2.6.orig/include/linux/mm.h 2010-10-19 14:19:40.000000000 +1100
> +++ linux-2.6/include/linux/mm.h 2010-10-19 14:36:48.000000000 +1100
> @@ -997,6 +997,10 @@
> /*
> * A callback you can register to apply pressure to ageable caches.
> *
> + * 'shrink_zone' is the new shrinker API. It is to be used in preference
> + * to 'shrink'. One must point to a shrinker function, the other must
> + * be NULL. See 'shrink_slab' for details about the shrink_zone API.
> + *
> * 'shrink' is passed a count 'nr_to_scan' and a 'gfpmask'. It should
> * look through the least-recently-used 'nr_to_scan' entries and
> * attempt to free them up. It should return the number of objects
> @@ -1013,13 +1017,53 @@
> int (*shrink)(struct shrinker *, int nr_to_scan, gfp_t gfp_mask);
> int seeks; /* seeks to recreate an obj */
>
> + /*
> + * shrink_zone - slab shrinker callback for reclaimable objects
> + * @shrink: this struct shrinker
> + * @zone: zone to scan
> + * @scanned: pagecache lru pages scanned in zone
> + * @total: total pagecache lru pages in zone
> + * @global: global pagecache lru pages (for zone-unaware shrinkers)
> + * @flags: shrinker flags
> + * @gfp_mask: gfp context we are operating within
> + *
> + * The shrinkers are responsible for calculating the appropriate
> + * pressure to apply, batching up scanning (and cond_resched,
> + * cond_resched_lock etc), and updating events counters including
> + * count_vm_event(SLABS_SCANNED, nr).
> + *
> + * This approach gives flexibility to the shrinkers. They know best how
> + * to do batching, how much time between cond_resched is appropriate,
> + * what statistics to increment, etc.
> + */
> + void (*shrink_zone)(struct shrinker *shrink,
> + struct zone *zone, unsigned long scanned,
> + unsigned long total, unsigned long global,
> + unsigned long flags, gfp_t gfp_mask);

Now we decided to don't remove old (*shrink)() interface and zone unaware
slab users continue to use it. so why do we need global argument?
If only zone aware shrinker user (*shrink_zone)(), we can remove it.

Personally I think we should remove it because a removing makes a clear
message that all shrinker need to implement zone awareness eventually.





\
 
 \ /
  Last update: 2010-10-19 06:51    [W:0.307 / U:0.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site